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Tree-ring reconstruction of June-July mean temperatures in the northern Daxing’an Mountains, China

Jiang Yangao, Wang Yu, Zhang Junhui, Han Shijie, Coombs Cassius E.O., Escobedo Maricely, Wang Junwei, Wang Xiaoguang, Hao Lin, Li Guode, Tong Yijiang, Gu Yue, Dong Shengzhong, He Haisheng, Yang Jingyu

Geochronometria

2020

Vol. 47, no.1

13--22

In this study, the mean temperature of June to July was reconstructed for the period of 1880 to 2014 by using the Larix gmelinii tree-ring width data for the Mangui region in the northern Daxing’an Mountains, China. The reconstruction accounts for 43.6% of the variance in the temperature observed from AD 1959–2014. During the last 134 years, there were 17 warm years and 17 cold years, which accounted for 12.7% of the total reconstruction years, respectively. Cold episodes occurred throughout 1887–1898 (average value is 14.2°C), while warm episodes occurred during 1994–2014 (15.9°C). Based on this regional study, the warmer events coincided with dry periods and the colder events were consistent with wet conditions. The spatial correlation analyses between the reconstructed series and gridded temperature data revealed that the regional climatic variations were well captured by this study and the reconstruction represented a regional temperature signal for the northern Daxing’an Mountains. In addition, Multi-taper method spectral analysis revealed the existence of significant periodicities in our reconstruction. Significant spectral peaks were found at 29.7, 10.9, 2.5, and 2.2 years. The significant spatial correlations between our temperature reconstruction and the El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO) and Solar activity suggested that the temperature in the Daxing’an Mountains area indicated both local-regional climate signals and global-scale climate changes.

Tree-ring based temperature reconstruction for the west Qinling Mountains (China): linkages to the High Asia, solar activity and Pacific-Atlantic Ocean

Chen F., Yuan Y., Wei W., Yu S., Shang H., Zhang T., Zhang R., Wang H., Qin L.

Geochronometria

2014

Vol. 41, no. 3

234--244

We developed a Faxon fir (Abies faxoniana) tree-ring width chronology at the timberline in the western Qinling Mountains, China. Herein February–July mean temperature was reconstructed for Zhouqu in the western Qinling Mountains back to AD 1650 based on the standard chronology. The climate/tree-growth model accounts for 43.5% of the instrumental temperature variance during the period 1972–2006. Spatial correlation analyses with the gridded temperature data shows that the tem-perature reconstruction captures regional climatic variations over central and southeast China, and strong teleconnections with the nearby High Asia. There is a good agreement with cold and warm pe-riods previously estimated from tree-rings in Nepal, India and southwest China. The temperature re-construction indicates that there was pronounced cooling in Zhouqu during the Maunder Minimum (late 1600s to early 1700s). The cold period (1813–1827) of the temperature reconstruction coincide with the volcanic eruptions. Significant spectral peaks are found at 56.9, 22.3, 11.4, 2.9, 2.8, 2.6, 2.2 and 2.0 years. The spatial correlation patterns between our temperature reconstruction and SSTs of the Atlantic and Pacific Oceans suggest a connection between regional temperature variations and the atmospheric circulations. It is thus revealed that the chronology has enough potential to reconstruct the climatic variability further into the past.

Reconstruction of crystallisation temperature of artificially grown H-analcimes by means of the IR and fluid inclusion studies

Słaby E., Kozłowski A.

Acta Geologica Polonica

2002

Vol. 52, nr 4

385-394

A method of reconstruction of the crystallisation temperature (Tc) of analcime has been proposed. The method is based on the compilation of two data sets: the IR absorption spectra and fluid inclusion study results. The water position in the analcime structure depends on the crystallisation temperature. Certain bands in the IR absorption spectrum are sensitive to the change in the temperature conditions of the analcime formation. Moreover, the IR absorption band positions are also influenced by the composition of the crystallisation system as well as by the crystallisation time. For more precise information about Tc, fluid inclusion studies were performed. They provide additional data about salt concentrations in the crystallisation system, water behaviour in the analcime structure and crystallisation temperature.